As a young man, Winchester operated a men’s furnishing store in Baltimore until 1848, when he set up a factory in New Haven to manufacture dress shirts. Financial success enabled him to purchase the Volcanic Repeating Arms Company of New Haven in 1857, soon reorganized as the New Haven Arms Company and, in 1867, as the Winchester Repeating Arms Company.

Benjamin Tyler Henry, Winchester’s factory superintendent, designed and patented the lever-action Henry repeating rifle and its self-contained metallic cartridge in 1860. That was the direct forerunner of a long line of Winchester arms, including the famous Models 1866 and 1873, favourite weapons of the settlers in the American West.

Following Winchester’s death, his company prospered during the latter 1880s and ’90s through the acquisition of advanced repeating long-arm mechanisms designed by John Moses Browning (Models 1886, 1890, 1892, 1893, 1894, 1895, and 1897). During the 20th century the Winchester enterprise became the leading manufacturer of sporting long arms and an important contributor to small arms and ammunition production in both World War I and World War II. Winchester was also noted for his philanthropy, particularly to Yale University.